1. Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK.
2. Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA.
3. Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA.
4. Department of Statistics, 1 South Parks Road, University of Oxford, Oxford OX1 3TG, UK.
5. Howard Hughes Medical Institute, University of Chicago, Chicago, IL 60637, USA.
6. Oxford Biomedical Research Centre, Nuffield Department of Medicine, University of Oxford, Oxford OX3 9DU, UK.
7. Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA 94143–0912, USA.
8. Department of Comparative Genetics and Refinement, Biomedical Primate Research Center, Lange Kleiweg 139 2288 GJ, Rijswijk, Netherlands.
9. Department of Ecology and Evolution, University of Chicago, Chicago, IL 60637, USA.